Crop & Pest Report

Accessibility


| Share

Spraying when it’s Breezy (6/04/20)

The extension specialists meet weekly during the growing season to discuss timely pest management and agronomic topics.

The extension specialists meet weekly during the growing season to discuss timely pest management and agronomic topics. Every year about this time someone will ask Daryl Ritchison, Director of the North Dakota Agricultural Weather Network, “it sure seems like it has been windy this season. How do winds compare to other years?”

Are there adjustments one can make to spray equipment to minimize off-target movement when conditions are breezy? Spray nozzles is the logical place to start. Consider reading the NDSU publication ‘Selecting Spray Nozzles to Reduce Particle Drift’ (AE1246, July 2017). Sprays can be successfully completed provided we consider the following steps:

  • Nozzle Selection. Droplet size is influenced by nozzle type and orifice size. Low-drift nozzles are designed to produce larger spray droplets with fewer driftable fines. Larger droplets are produced with the use of a pressure-reducing chamber inside the nozzle and with several nozzles by incorporating air into the spray droplets. These nozzles are excellent at reducing drift but will not eliminate all drift. Examples of such nozzles are Turbo TeeJet and AIXR TeeJet nozzles (Spraying Systems Co. http://www.teejet.com/), Hypro Ultra Lo-Drift and GuardianAir nozzles (http://www.hypropumps.com/), and the TurboDrop nozzles (Greenleaf Technologies http://www.greenleaftech.com/). Full Disclosure. The pesticide label may require use of specific nozzles that produce a coarse or medium-sized droplet.
  • Reduce spray pressure. Reducing spray pressure creates larger droplet sizes. Be aware that spray nozzles can produce different droplet sizes at different pressures. A nozzle might produce medium sized droplets at low pressure but fine droplets at higher pressure.
    • Increase carrier volume. Greater carrier volume is usually accomplished by selecting spray nozzles with a larger orifice. Spraying at 15 gallon per acre instead of 10 gallons or less per acre will reduce spray drift by creating larger droplets.
    • Adjust the spray boom height. The higher the boom, the greater the drift potential. Adjust the boom to the height required by nozzles to achieve the appropriate spray pattern and overlap.
    • Reduce sprayer ground speed. Spraying at greater speeds will cause the boom to bounce and spray vortex to occur, sending spray droplets higher in the air.
    • Use drift reduction agents. There are many effective products on the market contributing to reduce drift. However, some drift reduction agents are not compatible with certain low drift nozzles.

 

Tom Peters

 Extension Sugarbeet Agronomist

NDSU & U of MN

This site is supported in part by the Crop Protection and Pest Management Program [grant no. 2017-70006-27144/accession 1013592] from the USDA National Institute of Food and Agriculture. Any opinions, findings, conclusions, or recommendations expressed are those of the website author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture.

USDA logo

Creative Commons License
Feel free to use and share this content, but please do so under the conditions of our Creative Commons license and our Rules for Use. Thanks.